Methane ices pose climate puzzle (BBC) {new findings complicate picture}

[eppur_se_muova]

By Jonathan Amos
Science reporter, BBC News, San Francisco

Scientists drilling ocean sediments off Canada have discovered methane ices at much shallower depths than expected.

The finding has important implications for climate studies, they believe.

The melting of hydrates, as they are known, is a suspected contributor to past and present increases in atmospheric methane, a greenhouse gas.

If shallow ices are destabilised in a warming world, it could have a positive feedback effect and drive temperatures even higher, the researchers warned.

"The rate of increase in the Earth's atmosphere for methane is much faster than that for carbon dioxide," said Timothy Collett, the co-chief scientist of the Integrated Ocean Drilling Program (IODP).
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more: http://news.bbc.co.uk/2/hi/science/nature/6166011.stm

[xchrom]

1. hmmm -- interesting -- using the methanes in ice

as an energy source?

there are probably reasons for not doing that -- i.e. some of that ice sounds hard to get to -- but the article doesn't point out the negatives.

[bananas]

2. You can make flaming snowballs from it.

[lostinacause]

12. It is likely the case that the concentrations are too low.

[BeFree]

3. Methane

How much methane could humans tolerate in the air we breathe?

It may be that the air pollution from the thawed methane would bring an end to most life forms?

[Javaman]

4. I don't know, but after last months chili festival, I couldn't stay in that room

a minute longer...

:rofl:

[GliderGuider]

5. The chemical aspects of the polution aren't the big problem

The problem is that the stuff is a very potent greenhouse gas, and the potential exists for a runaway effect to start. As well as being found under the sea floor this ice is also buried in permafrost in Siberia and Canada. If the permafrost starts to thaw, it will release the methane, which then traps more heat, thawing more permafrost, releasing more methane, which traps more heat... Long before the methane poisons us it would raise the temperature high enough to significantly damage the biosphere.

Given the amount of methane thought to be frozen into the world's permafrost, this is really a nightmare scenario. Especially since the permafrost is known to be thawing already. If the ice is closer to the surface than we at first thought, asmthis article implies, the time of risk moves significantly closer.

[BeFree]

11. 'Preciate that, but

That wasn't an answer to my question. We know that as the methane hydrates are released it will trigger even more releases. My question is at what point would methane in the atmosphere become poisonous to air breathing fauna? Especially homo sapiens. Thanks.

[lostinacause]

13. If it was an issue someone would have likely said something about it.

I have yet to hear someone mention it.

[GliderGuider]

15. Sorry, here's some info on methane toxicity

According to the document Emergency and Continuous Exposure Limits for Selected Airborne Contaminants, Volume 1 (2000), methane is considered biologically inert. There is no known toxicity, and any physiologically deleterious effects come from oxygen displacement. According to another site, methane is classified as a "simple non-toxic asphyxiant". So the dangers at even very high atmospheric concentrations would seem to be limited to its greenhouse action.

[BeFree]

16. Thank you GliderGuider

Here's what I found:

SUMMARY OF TOXICITY INFORMATION . Little information is available on the toxicity of methane. It appears that toxic effects of methane, considered biologically inert, are related to the oxygen deprivation that occurs when the simple alkane is present in air at a high concentration. Hunter ( 1978) stated that miners evacuate coal pits when the methane concentration in air reaches 2.5% by volume;

It would take a hell of a lot of methane to bubble to the surface to reach 2.5% volume, eh?

It's a wonder that there hasn't been some studies of coal miners who were exposed to methane for periods of time. Thanks again, GG.

[progressoid]

6. And with typical head-in-the-sand mentality...

Man ignores that "Methane is 20 times more effective as a greenhouse gas than CO2 and just sees $$ in the short term:

Hydrates have naturally excited the attention of mineral companies, and a number of them are now investing considerable sums of money in trying to exploit the resource.

BP will begin an exploratory programme to drill hydrates under the Alaskan permafrost in the New Year.

[dapper]

7. Question- Capturing Methane

I thought about this the other day, is there any thought of capturing/containing this methane for fuel use? I imagine it would be a huge undertaking but would it not be better to capture as much methane as we could to avoid the hit on the environment.

Burning Methane would produce CO2 but we could always experiment with it to convert it to cleaner fuel?!? I'm not an expert here so I will let you guys toss this around but I would love more info on it.

Dapper

[Dead_Parrot]

8. Methane capture is being looked at

Although AFAIK only for dense deposits - the spread-out clathrates in the tundra and most of the oceanic deposits are too disperse to do anything with, so they're going to do what they like anyway.

As for the conversion to a cleaner fuel, methane is CH₄ - you could split it to make hydrogen, which is nice and clean, but the carbon is still released as CO₂ - just at the point of manufacture rather than the point of use, so you are not any better off.

Methane is a more powerful GHG than CO₂, so there is a sort of twisted logic to burning it rather than letting it be released, but it's the same sort of logic that says being stabbed through the heart is better than being stabbed through the heart with a poisoned blade - a third alternative would be preferable.

Good questions, though, and someone may tell me I'm wrong. :)

[dapper]

9. a slow burn...

These are the things we will probably need to research going forward. CO2 or Methane- it definately is a tough choice. Of course if we can find a solution to making it a cleaner fuel. Maybe they can use it on the Space Station they plan to build on the moon?

Dapper

[buddysmellgood]

10. We tap landfill with pipes, collect the methane and use it for fuel. The third option might be

sequestering the carbon.

[XemaSab]

17. You could use the CO2 for enhanced methane recovery.

Good times. :D

[lostinacause]

14. If you end up replacing fossil fuel use with methane it would be a step

in the right direction. Conservation and innovation will be the key in the big picture but in the mean time replacing CH4 with CO2 is a good idea.